Bal·loon n.
 1. A bag made of silk or other light material, and filled with hydrogen gas or heated air, so as to rise and float in the atmosphere; especially, one with a car attached for aërial navigation.
 2. Arch. A ball or globe on the top of a pillar, church, etc., as at St. Paul's, in London. [R.]
 3. Chem. A round vessel, usually with a short neck, to hold or receive whatever is distilled; a glass vessel of a spherical form.
 4. Pyrotechnics A bomb or shell. [Obs.]
 5. A game played with a large inflated ball. [Obs.]
 6. Engraving The outline inclosing words represented as coming from the mouth of a pictured figure.
 Air balloon, a balloon for aërial navigation.
 Balloon frame Carp., a house frame constructed altogether of small timber.
 Balloon net, a variety of woven lace in which the weft threads are twisted in a peculiar manner around the warp.